:~$ sudo efibootmgr -b 2003 -B
boot entry: 2003 not found
Et pourtant :
:~$ sudo efibootmgr -v
BootCurrent: 0000
Timeout: 0 seconds
BootOrder: 3003,3000,2001,2002,2003
Boot0000* Ubuntu HD(1,800,79800,03bba9b9-1ba3-4302-98c4-6441cc659e1c)File(\EFI\ubuntu\grubx64.efi)RC
Boot0003* Windows Boot Manager HD(1,800,79800,03bba9b9-1ba3-4302-98c4-6441cc659e1c)File(\EFI\Microsoft\Boot\bootmgfw.efi)RC
Boot2001* USB Drive (UEFI) RC
Boot2002* Internal CD/DVD ROM Drive (UEFI) RC
Boot3000* EFI Internal Hard Disk or Solid State Disk RC
Boot3003* EFI Internal Hard Disk or Solid State Disk RC
Ce qui est curieux, puisque j'ai bien passé ton
efibootmgr -o 0000,3003,3000,2001,2002
sous live USB